CNET's Greg Sandoval reports that Googlers are now testing the music service internally. This follows a report from earlier this month that some users of rooted Android phones were able to access the service.

Google Music isn't just another digital music store: rumor has it that Google wants to launch a digital locker and allow users to put their entire music libraries online for access from any device.

And that's exactly why these Google Music rumors keep popping up without actually coming to fruition. As Sandoval explains, even though the storage service is up and running within Google, negotiations with record labels remain unresolved. It's a tricky situation, because labels are moving into uncharted territory--the licensing of music to be accessed anywhere--and they're skittish about acting too hastily.

Even so, the labels do want Google to be a player in digital music. In their minds, Apple has become too powerful, with iTunes accounting for 66 percent of digital music sales as of December. Where Amazon has failed to become a true competitor, the labels hope Google can succeed. They're just too scared about the digital locker to make it happen.

Sandoval and others think that Google could launch the music service at its Google I/O developers conference in May, but that's just speculation. And as we've seen time and time again, it's dangerous to speculate about when tech companies and record labels will get on the same page. The rumor mill has also predicted a competing digital locker service from Apple that's yet to materialize. I'm not holding my breath for either.

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